Sealant packaging and method

ABSTRACT

An improved sealant packaging and method for use with sealing joints and cracks in pavement and parking lots is provided. Liquid sealant material is poured by volume into a container draped with a sheet. Container is cooled so that the sealant becomes a solid block, with the sheet adhered to the sides of the sealant block such that the sheet forms a container for the sealant. The sheet also acts a release liner for easily removing the sealant block from the container. Two or more contained blocks are stacked together, forming a package of two or more blocks self-sealed by sheets. When the package is placed in a melting kettle, heat migrates through the spaces between the individual sealant blocks and allows the smaller sealant blocks to melt quickly and evenly. Sheet and film melt with sealant material and are incorporated therein to form the final sealant product.

CROSS-REFERENCE

This application claims the benefit of U.S. Provisional PatentApplication No. 61/678,490 filed on Aug. 1, 2012, which is incorporatedherein in its entirety.

BACKGROUND

Sealants are used for the sealing of joints and cracks in concrete andasphaltic pavements and parking lots. It is known in the art to deliverpackaged blocks of sealant material to a job site, which are then meltedin a kettle on-site. The liquefied melted sealant is then used to sealjoints and/or fill cracks in the pavement. It is also known in the artto use a material for the packaging that itself is an ingredient forincluding into the sealant product. Prior art which describes such asystem is U.S. Pat. No. 8,017,681 to Guymon et al., which disclosesadding a thermoplastic product to a foamed polymer container, the foamedpolymer container being an ingredient in the sealant product such thatthe entire container and its contents can be placed in a kettle on thejob site and melted. However, foamed polymer containers are expensive,and must be separately transported and stored in preparation for thesealant packaging process. Moreover, the foamed polymer container causesproblems as it melts with the sealant in the kettle on-site. Also knownis the use of less bulky polypropylene film as packaging, as describedin U.S. Pat. No. 5,452,800 to Muir for use with roofing asphaltapplications. In Muir, a mold with dimensions to produce a 50-poundasphalt block is lined with polypropylene film, liquid asphalt is pouredinto the lined mold, and the mold is cooled. When the asphalt is cooledto solid, the asphalt covered by the polypropylene film is removed, thefilm forming the packaging for the asphalt block which then melts withthe asphalt is heated in the on-site vat. A portion of the top of eachasphalt block is left uncovered by the film, such that when packages arestacked the top asphalt surface of a package will adhere to the bottomof an adjacent package. However, Muir does not disclose use of such apackaging method for joint sealant material. Moreover, Muir disclosesforming a single, large block of asphalt material for melting on-site,which results in a slow melting time due to the required heating for alarge solid block of material.

SUMMARY

The present invention solves the existing limitations. The presentinvention relates to an improved sealant packaging and method for usewith the sealing of joints and cracks in concrete and asphalticpavements and parking lots. In particular, the present inventionprovides a method of forming a package of two or more blocks of sealant,wherein multiple blocks of sealant are contained by a sheet ofpolypropylene and form a self-sealed package of multiple blocks formelting in a kettle on the job site. The polypropylene sheet acts as aninexpensive, easily stored container for the sealant, and can also bemelted into the sealant mix at the job site. In a preferred embodiment,sealant material is liquid at pour temperature and is dispensed byvolume into aluminum pans lined with a sheet of polypropylene or similarmaterial. As the sealant fills the pan the sheet repositions itselfagainst all open sides of the pan, with the sealant taking the shape ofthe pan. The filled pan is then cooled so that sealant becomes a solidblock of material, covered on all sides except the top surface of theblock by the polypropylene sheet such that the polypropylene sheet formsa container for the sealant. The polypropylene sheet also acts a releaseliner for easily removing the sealant blocks from the pan. A secondblock is formed in the same manner, and two or more contained blocks arethen stacked together, with the open ends of two blocks placed adjacentto one another, and the open sides of any additional blocks placed onthe bottom of the stack of two, forming a self-sealed package of two ormore blocks. The package of two or more blocks is then sealed togetherwith a film, such as by shrink-wrapping, and delivered to the job site.When the package is placed in a melting kettle, heat migrates throughthe spaces between the individual sealant blocks unlike prior systemswhich use a single, large block sealant material, and allows the smallersealant blocks to melt more quickly and evenly in the kettle.

Other objects, advantages, features, properties and relationships of theinvention will be obtained from the following detailed description andaccompanying drawings which set forth illustrative embodiments that areindicative of the various ways in which the principles of the inventionmay be employed.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a top perspective view of a container for receiving a volumeof sealant material in accordance with the present invention;

FIG. 2 is a top perspective view of a container lined with a sheet forreceiving a volume of sealant material in accordance with the presentinvention;

FIG. 3 is a top perspective view of a container lined with sheet andfilled with sealant in accordance with the present invention;

FIG. 4 is a top perspective view of a block of cooled sealant removedfrom container and covered with sheet in accordance with the presentinvention;

FIG. 5 is a top perspective view of three blocks of cooled sealantstacked together in accordance with the present invention;

FIG. 6 is an exploded view showing three blocks of cooled sealant beforeand after stacking together in accordance with the present invention;

FIG. 7 is a top perspective view of three blocks of cooled sealantstacked together and wrapped in a film in accordance with the presentinvention; and

FIG. 8 is a flowchart illustrating a method of packaging a sealantproduct in accordance with the present invention.

DETAILED DESCRIPTION

The description that follows describes, illustrates and exemplifies oneor more embodiments of the present invention in accordance with itsprinciples. This description is not provided to limit the invention tothe embodiments described herein, but rather to explain and teach theprinciples of the invention in order to enable one of ordinary skill inthe art to understand these principles and, with that understanding, beable to apply them to practice not only the embodiments describedherein, but also other embodiments that may come to mind in accordancewith these principles. The scope of the present invention is intended tocover all such embodiments that may fall within the scope of theappended claims, either literally or under the doctrine of equivalents.

Referring now to the FIGS., a representative embodiment of the presentinvention is illustrated that includes a sealant product and packagingmethod therefore. In FIG. 1, a generally rectangular container 20, suchas pan comprised of aluminum or similar material, is configured toreceive a volume of sealant material 10. Sealant material 10 maycomprise any suitable composition appropriate for filling cracks andjoints in concrete and asphaltic pavements. One example of a suitablesealant material 10 is a petroleum asphalt, petroleum oil, thermoplasticpolymer and limestone-based composition. Sealant material 10 is liquidat pour temperature such that it fills the volume and shape of pan 10when poured into pan 20, and cools to a solid when cooled at or about125° F. In a preferred embodiment, pan 20 is sized to create finishedsealant blocks 10 weighing approximately 10 lbs. Exemplary dimensions ofthe pan 20 in this embodiment are 3″×14″×22″. In this embodiment, threeindividual sealant blocks 10 are then self-sealed together (describedbelow) to produce an approximately 30-lb package 50, which permits easyhandling and also allows entire package 50 to fit into a melting kettle.Pan 20 can alternatively be sized to produce sealant blocks 10 ofvarying sizes, and, as a result, packages 50 comprised of varyingnumbers of sealant blocks 10 and having varying total weights.

As seen in FIG. 2, pan 20 is draped or lined with a sheet 25 ofpolypropylene or similar material. The sheet 25 acts as an inexpensive,easily stored flexible container for the sealant 10, and can also bemelted into a liquid state along with sealant material 10 andincorporated into the sealant product for use at the job site. To form ablock of sealant 10, liquid sealant 10 is poured into pan 20 over sheet25. As seen in FIG. 3, as the sealant 10 fills the pan 20, the sheet 25repositions itself against all sides of the pan 20. This repositioningis from the force of the sealant 10 self-leveling and taking the shapeof the pan 20. Sealant material 10 is compatible with the sheet 25material such that sheet 25 adheres to the sealant 10 after the sealant10 is poured into pan 20. In a preferred embodiment, sheet 25 iscomprised of extrusion grade polypropylene. As described below, sheet 25will turn to liquid when packaged sealant product 50 is placed in akettle on the job site, the sheet 25 forming part of the end product forfilling cracks and joints. The polypropylene comprises approximately0.2% of the joint sealant. Polypropylene is a long carbon chain withonly methyl functional groups, and is very compatible with asphalt.There are no significant chemical reactions that take place between thepolypropylene and other components of the joint sealant. When thepolypropylene breaks down it merely becomes part of the filler in thesealant. In a preferred embodiment shown in FIG. 3, sheet 25 is sizedsuch that when sealant 10 fills the pan 20 and repositions sheet 25,sheet 25 covers all sides of the sealant 10 and a portion of the topsurface of the solid block, leaving at least a portion of the topsurface exposed. Alternatively (not shown), sheet 25 can be sized withextra area around each side of pan 20 so that extra sheet 25 area can befolded over the top of the filled pan 20, also covering the top surfaceof the sealant 10 in addition to all surfaces inside the pan 20. Sheet25 protects sealant 10 from being exposed to the elements duringtransport and before use on the job site and allows easy handling of thesealant 10 for transport and placement into a melting kettle on the jobsite, all without requiring bulky Styrofoam or other solid containersfor the sealant 10.

After lined pan 20 is filled with liquid sealant material 10, filled pan20 is cooled to solidify the sealant 10. The sealant is sufficientlycool enough to handle and stack in the range of about 120° F.-130° F. Ina preferred embodiment, pan 20 is placed onto a steel belt which travelsthrough a water bath for initial cooling. A chiller may be used tomaintain water at a cold temperature. Pan 20 then undergoes additionalcooling, such as by passing cold air over the sealant 10. In a preferredembodiment, pan 20 is placed in a wind tunnel, which pulls large volumesof air across the top of the sealant 10 filled pans 20. Alternativecooling methods may be used, any of which provide accelerated cooling ofthe liquid sealant 10 to a solid state.

When sealant material is cooled to a solid state, a block 10 of sealantresults with sheet 25 is adhered to the sides of the sealant block 10and a portion of the top surface of the sealant block 10. As shown inFIG. 4, sealant block 10 covered with sheet 25 is then removed from thepan 20, the sealant block 10 now minimally packaged in the sheet 25 foreasy handling, with the sheet 25 not requiring removal from the sealantblock 10 before melting sealant block 10 in a kettle on the job site. Inaddition to providing packaging for the sealant block 10, the sheet 25also acts a release liner, allowing easy removal of the sealant block 10from the pan 20.

In a preferred embodiment shown in FIG. 4, when cooled sealant block 10is removed from pan 20 sheet 25 covers all sides of sealant block 10 anda potion of top surface 12 of block 10. As seen in FIGS. 5 and 6,multiple covered sealant blocks 10 are then sealed together to form aself-sealed package 50 of two or more sealant blocks 10. As shown inFIG. 6, to create package 50, two or more contained sealant blocks 10,10′ and 10″ are stacked together, with the at least partially uncoveredsurface 12 of two blocks 10 and 10′ placed adjacent to one another, andthe at least partially uncovered surface 12 of any additional blocks 10″placed on the bottom of the stack of two, forming a package 50 of two ormore blocks 10, 10′ and 10″ self-sealed by sheets 25.

As shown in FIG. 7, package 50 can optionally be further wrapped in afilm 60 comprised of a material which mixes together with sealantmaterial 10 and sheet 25 to become part of the end sealant product. Thisadditional film 60 ensures a complete seal around package 50 fortransport. In a preferred embodiment, self-sealed package 50 is placedin a shrink-wrap machine which wraps the package with film 60 comprisedof plastic material. The shrink wrap helps give the pallet stability andweather proofs the sealant. FIG. 8 is a flowchart illustrating theabove-described method of packaging a sealant product in accordance withthe present invention.

Placing self-sealed package 50 of multiple blocks 10 into melting kettlehas the key advantage of allowing sealant blocks 10 of package 50 tomelt faster and more evenly than current systems which use one largesealant block. When package 50 is placed in and oil-jacketed meltingkettle and heated to approximately 370° F., film 60, sheet 25 andsealant material 10 melt to form final sealant product. As sealantmaterial 10 begins to melt, package 50 separates. Melted sealantmigrates into the spaces between individual sealant blocks 10 and speedsup the melting process. This allows a greater surface area of the solidsealant material 10 to be exposed to hot liquid sealant more quickly,allowing package 50 to melt approximately two and a half times fasterthan traditional systems using one large block of sealant material. Theuse of multiple, smaller blocks 10 as opposed to one large block ofmaterial also allows blocks 10 to melt more evenly than melting onelarge block of material. When film 60, sheet 25 and sealant material 10are melted to liquid form and mixed together, the final sealant productis removed from the kettle and placed into cracks or joints of asphaltor pavement.

In a preferred embodiment described above, where a sealant block 10 isdimensioned to weigh approximately 10 lbs, three individual sealantblocks 10 are stacked together to form a three-block package 50 weighingapproximately 30 lbs. Packages 50 of this approximate size and weightfit into standard-sized melting kettles, and also allow for easy liftingof packages 50 from pallets or other means of transporting packages 50for placement into melting kettles on site. However, also consistentwith this invention are individual sealant blocks 50 formed in pans 20with varying dimensions to result in sealant blocks 50 with varyingsizes and weights. For example, packages of four blocks 10 weighingapproximately 8 lbs each and with a total package 50 weight ofapproximately 32 lbs may be formed. Or, sealant blocks 10 and packages50 of multiple blocks may be sized and packaged to accommodate varyingsizes of kettles, or preferred package 50 dimensions and weights asdesired by users.

While specific embodiments of the invention have been described indetail, it will be appreciated by those skilled in the art that variousmodifications and alternatives to those details could be developed inlight of the overall teachings of the disclosure. Accordingly, theparticular arrangements disclosed are meant to be illustrative only andnot limiting as to the scope of the invention which is to be given thefull breadth of the appended claims and any equivalent thereof.

What is claimed is:
 1. A method for packaging a sealant product, themethod comprising: providing a generally rectangular containerconfigured to receive a volume of sealant product; lining said containerwith a sheet of material, said material being capable of ultimateintegration into sealant product and also being capable of adhering tosaid sealant product when said sealant product is cooled to a solidstate; providing said volume of sealant product into container linedwith sheet; cooling said volume of sealant product to solidified sealantblock; removing sealant block and sheet adhered thereto from container;stacking two or more sealant blocks and sheets adhered thereto togetherto form a package of sealant blocks, wherein package may be placed intoa kettle for melting sealant product; and wherein heating package insaid kettle melts sealant block and sheet into a liquid state for use ofsealant product, said sheet being thereby integrated into sealantproduct.
 2. The method of claim 1, further comprising wrapping packagein a film, said film configured for integration into sealant product. 3.The method of claim 2, wherein the film is comprised of plastic.
 4. Themethod of claim 3, wherein the wrapping of said package comprisesshrink-wrapping.
 5. The method of claim 1, wherein container iscomprised of aluminum.
 6. The method of claim 1, wherein said sheet iscomprised of polypropylene.
 7. The method of claim 1, wherein saidcooling of said volume of sealant product comprises cooling said sealantproduct to a temperature within a range of about 120° F.-130° F.
 8. Themethod of claim 1, wherein sheet is sized to adhere to all except topsurface of sealant block.
 9. The method of claim 1, wherein sheet issized to adhere to all surfaces of sealant block and further comprisingthe step of folding sheet over top surface of sealant product afterproviding said volume of sealant product into container lined withsheet.
 10. The method of claim 1, wherein said heating of said packagecomprises heating said sealant product to a temperature within a rangeof about 370° F.-390° F.
 11. A method for packaging a sealant product,the method comprising: providing a generally rectangular containerconfigured to receive a volume of sealant product; lining said containerwith a sheet of material, said material having a composition suitablefor integration into sealant product and also capable of adhering tosaid sealant product when said sealant product is cooled to a solidstate; providing said volume of sealant product into container linedwith sheet; cooling said volume of sealant product to solidified sealantblock; removing sealant block and sheet adhered thereto from container;stacking two or more sealant blocks together to form a package ofsealant blocks and adhering sheets, wherein package is adapted forplacement into a kettle for melting sealant product; wrapping package ina film, said film having a composition suitable for integration intosealant product; and wherein heating package in said kettle meltssealant block, sheet and film into a liquid state for use of sealantproduct, said sheet and said film being integrated into sealant product.